August 8, 2005 - A new high-resolution camera is set to depart for the planet Mars Wednesday morning aboard NASA’s Mars Reconnaissance Orbiter. The camera, the High Resolution Imaging Science Experiment (HiRise) is the largest camera ever sent out of Earth’s orbit and will deliver the highest resolution images of Mars yet.
"We expect the HiRise camera to provide very high quality imagery for both scientific research and NASA’s future mission planning," said Dave Taylor, CEO and President of Ball Aerospace & Technology, who built the camera for the University of Arizona.
The camera utilizes a series of mirrors and lenses that project the image onto a cluster of CCDs rendering images with a resolution up to 20,000 pixels by 40,000 lines, an image so large that it would take 1,200 typical computer screens to fully display. The camera’s high resolution will enable the identification of objects as small as a coffee table while the camera orbits 300 kilometers above the planet’s surface.
The camera’s high resolution is garnered by a combination of advanced optics and electronic wizardry. A 50 centimeter primary mirror magnifies images that enter the camera through its 1.4 meter long telescope tube. The image is then bounced off two other mirrors and focused onto the camera’s detector chip assemblies (DCA), which each house 14 CCDs that actually record the image. One of the key features of the camera’s electronics is its high 100:1 signal to noise ratio, enabling it to render more useful images, with minimal noise and maximum clarity.
The DCAs are able to capture a variety of image types including black and white and color photographs, as well as stereo-images and 3D models of the planet’s surface. The camera’s field of view is about six kilometers across, with each pixel in the image representing about 30 centimeters of Mars’ surface. Due to the large images produced by the camera, it will take anywhere from 4 to 48 hours to transmit a high-resolution image to Earth, depending on the distance to Earth and the compression applied to the image.
NASA plans to capture over 1,000 high-resolution and 9,000 lower resolution images over the planned four years of the mission, which is set to begin once the craft enters Mars’ orbit in March, 2006. The Mars Reconnaissance Orbiter, however, has enough fuel to extend the mission until 2014.
Along with the HiRise camera, the Mars Reconnaissance Orbiter will carry two other cameras, a spectrometer, a radar instrument for looking below the planet’s surface and a radiometer. In addition to capturing images of Mars’ surface, scientists also plan to use the camera to find suitable landing sites for future missions, including the Phoenix Mission, which plans to land on Mars in 2008.